<form action="${request.contextPath}/admin/add" name="form1" id="form1" method="post">
    商品名称:<input type="text" name="itemname" id="itemname"><br>
    商品价格:<input type="text" name="price" id="price"><br>
    商品个数:<input type="text" name="counts" id="counts"><br>
    商品品牌:<input type="text" name="brand" id="brand"><br>
    商品PD:<input type="text" name="PD" id="PD"><br>
    <input type="hidden" name="cid" id="cid" value="${cid}">
    <input type="submit" name="submit" id="submit" value="提交">
</form>